Diguanidine



' Patented Nov. 26, 1929 PATENT OFFICE v mvnorf HEYN, or BBESLAU,

GERMANY, ASSIGNOB, BY MESNE ASSIGNMENTS, 'ro THE FIRM SCHERING-KAHLBAUM A. (3., OF BERLIN, GERMANY DIGUANIDINE No Drawing. Application filed July 16,

- My invention has reference to new derivatives of guanidine' which: have been shown to be of great value for the treatment of certain diseases. '5 polymethylene diguanidines which were hitherto unknown. A number of methods for producing derivatives of guanidine were known, amongst them the reaction of cyanamide with amino salts discovered by Erlenmeyer (Berichte 14, 1868/1881) In this reaction there are formed, besides the monoguanyl derivatives also diguanidines. In my copending application for Letters Patent of the United States, Serial No. 125,-

- 322, I have described a method of producing pure monoguanylized diamines.

I have now discovered that diguanidine derivati-ves can be obtained in a more simple vmanner and with better yield by causing" mols of S-alkyl i'sothiourea to act on a d1 amine. The complete reaction takes place at ordinary temperature, and if a S-alkyl-isothiourea'is used under the form of a salt, the crystalline salt of the respective diguanidine is at once obtained. a

The new method is particularly valuable for the production of higher' alkylene diamines, the low so ubility of which-creates difliculties' when preparing these products according to the methods hitherto employed..

Example 1 Aiconcentrated solution of 5 parts weight of hexamethylene parts S-methyl-isothiourea-sulfate in water. 40 The mixture is heated on the water bath until no more methyl mercaptane escapes.

whereupon the mixture is acidified with dilute sulfuric acid and well cooled. -80 per cent hexamethylene diguanidine' sulfate 4 are obtained.

It more particularly refers to 5 parts by weight of diamine is grad-I ually added to a concentrated solution of 12 1926, Serial No. 128,009, and in Germany August 4, 1925.

The reaction taking place may be represented as follows: 1 NH zit-serialized l NH: H: The crystalline product is decomposed by, concentrated caustic alkali under development of ammonia. It cannot be distilled. sulfate melts above 280 ride at 181-182 C. The picrate dissolves in water only with difliculty.

v Example $2 0 A concentrated watery solution containing decamethylene diamine is gradually added to a concentrated watery solution of 8 parts S-methyl isothiourea sulfate and the mixture is treated further as {described with reference to Example 1., There are obtained 5080 per cent decameth'ylene-diguanidine sulfate according to the following formula Nnr-(cHmr-NH, 2l::-s-c11,.1-'

(CH1) m-NH =NH t=NH I l l'Ha H1304 NH:

The product forms a crystalline mass. The sulfate melts above 280, the hydrochloride at 198-200 C. The picrate dissolves. in water only with difliculty.

In the claims appended to the specification the terms polymethylene diguanidines and decamethylene diamine are intended to in clude also the salts of these compounds.

Various changes may be made in the details disclosed in this specification without departing from the invention or sacrificing the advantages thereof.

The (l, the hydrochlo- I claim 1. As new products, polymethylene diguanidines having the formula HN 011, NH 5 $=Nm =NH NB: NB!

wherein m is a whole number above 5, the products being decomposed by concentrated caustic alkali under development of ammonia,

being incapable of being distilled and forming crystallized salts, the pictrates being soluble only with great difliculty. v a

2. As a new product decamethylene diguanidine having the formula:

2 the hydrochloride melting at 198200 (l, the sulfate melting above 280 C. and forming a picrate dissolving in water only with great difiiculty, treatment with concentrated caustic alkali causing the splitting 01f of ammonia.

In testimony whereof I have signed my name to this specification.

v MYRON HEYN. 

